During semiconductor wafer fabrication, electrically conductive active area contacts are formed between active areas at the substrate level of the wafer and electrically conductive interconnect lines located above the substrate level. Also, electrically conductive gate contacts are formed between transistor gate structures within the wafer and electrically conductive interconnect lines located above the gate structures. Conventional active area contact and gate contact fabrication methods have relied upon photolithographic techniques in which a photomask is used to project a light pattern onto a photoresist layer deposited on the wafer, so as to transfer the pattern to the photoresist layer, wherein the pattern defines various openings within the photoresist layer at which contacts are to be formed. The various contacts are required to be accurately aligned to the underlying active areas and gate features for proper contact placement, and ultimately for proper device operation. Therefore, the photomask must be accurately aligned to the wafer to enable proper transfer of the contact pattern onto the wafer.
As device sizes become smaller and their features become more closely spaced on the wafer, contact placement and fabrication becomes more difficult. For example, it becomes more difficult to satisfy the increasing photomask-to-wafer alignment accuracy requirements. Therefore, it is of interest to seek methods by which contacts can be more accurately placed and fabricated for devices having smaller and more closely spaced features.